| KB0SFP |
Rating:     |
2009-02-10 | |
| Good but needs refinement |
Time Owned: 6 to 12 months. |
I purchased two of these for around $50ea from W0BW at a hamfest last summer($30 less than they sell on Ebay).
I have used the pair as a tripod mounted dipole on 40 & 20 meters(Pictures available). I have also used them as a tripod mounted vertical, & as the whip on PM HFpack sets. In all cases the antenna performed well. I had the below exchange of emails with the Opek company shortly after some extensive use last summer. If after their "market study" they should decide to redesign the antenna to cover 60 meters & WARC bands better I would by another pair of antennas(I think they are that good).
If you too have an interest in a design change you might also email the below persons with your sentiments as well.
KB0SFP
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I just purchased two of your antennas new at a hamfest.
At first glance I was very happy to get them.
Then after trying to use them I found several things that bothered me.
#1, no 60 mtr operation.
#2, no 17 mtr operation.
#3, when the antenna was adjusted for operation on 3.885mhz on 75mtrs the other bands were as follows:
40mtr position moved to 7.750mhz
20 mtrs 14.600mhz
15 mtrs 18.8mhz
10mtr 31.5mhz.
So, to change bands it was required to readjust the resonator every time. I found that the supplied frequency adjust chart was not even in the ball park on either of my antennas.
#4, The antennas that I purchased are fitted with PL-259 type bases. a 3/8 x 24 thread base would have been far more versatile & functional. Adapters to go from 3/8 x 24 to PL-259 are very common should the owner wish that type connection. This is all the salesman had, I do not know if you offer this antenna is 3/8 x 24 or not.
This is were I stand & from what I've read on the net, most Hams feal the same way.
#1, given the chanse to buy another HVT-400 in it's current configuration, I would not!
#2, if a new version of the HVT400 existed that included taps for ALL US amateur including 60, 17, 12 meters), & that had a center frequency on each band tap that was closer to one that's usable(reduced need to retune on each band), & if it had a 3/8 x 24 threaded base, I would buy several more. So please fix your design.
Dennis Starks
KB0SFP
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James R. Baehr
OPEK TECHNOLOGIES, INC.
PH: 803-775-7100
FAX: 803-775-7114
http://www.opektech.com
ATTN: Mr. Dennis Starks, 09/10/08
We have forwarded your E-mail to our factory, with your suggestions.
Thank you,
James R. Baehr/ Opek Technologies, Inc
------------------------------------------
DEAR MR. DENNIS STARKS,
WE APPRECIATE VERY MUCH YOUR PRECIOUS COMMENTS ABOUT OUR HVT-400B ANTENNA. AFTER CAREFULLY STUDIED YOUR COMMENTS, WE UNDERSTAND YOU ACTUALLY NEED A COMPLETELY DIFFERENT ANTENNA WHICH HAS SIMILAR CONSTRUCTION AND APPEARANCE OF OUR HVT-400B ANTENNA.
*FOR ECONOMICAL SCALE OF PRODUCTION AND MARKETING/SALES, WE'LL HAVE TO DO A MARKET SURVEY TO SEE IF THERE IS A SUFFICIENT DEMAND. IF YES, THEN WE WILL TRY OUR BEST TO DESIGN A NEW VERSION OF OUR HVT-400B ANTENNA FOR CUSTOMERS' SATISFACTION IN THE FUTURE.
HAVE A NICE DAY W/BEST REGARDS,
AUTOTEK LTD. / CHARLES WU
CW/rh
From: "AUTOTEK" autotek@ms1.hinet.net Cc: Date: Thu, 11 Sep 2008 19:23:53 +0800 Subject: Re: Opek HVT-400 antenna
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| KE7FD |
Rating:     |
2008-08-04 | |
| After repaired: works better than before |
Time Owned: more than 12 months. |
| I have used the repaired antenna on 40 and 20 meters so far. It loads up fine once the whip is adjusted. Using my TS-480, I set the antenna SWR as low as possible before engaging the tuner. (I have a very short length of coax between the radio and the antenna, wavelength speaking: 4 feet max.). Without the internal tuner, the antenna offers a narrow bandwidth with required re-tuning of the whip to use it on different bands. My recommendation for this antenna is to compliment it with HF rigs (or tuners) that can be located near the antenna to maximize the effectiveness of the tuner: This antenna needs all the help it can get, unless it'll be used without changing frequency very much. |
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| KM3DR |
Rating:      |
2008-02-12 | |
| Good for portable use |
Time Owned: more than 12 months. |
| When I saw the antenna for the first time, I had to test one at the price. The first thing I did was cut the top portion off and mount a 3/8-24 stud. Clamped to a table with counterpoise wire it tuned up perfectly. I've not had any problem loading it on any bad and have been succesful making contacts with as little as 10 watts SSB. I've never planned on using it mobile, but or small portable set-ups i get a lot of bang for the buck. I have a second one wiating to be used after I use up the first one. |
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| N8ERM |
Rating:  |
2008-02-04 | |
| Poor mechanical construction. |
Time Owned: 0 to 3 months. |
I had one of these for three weeks and it failed. It was replaced by the dealer. The second one lasted less than two months. The dealer commented that he had quite a few failures to send back to the OEM.
Why sell em?????
I replaced it with a Little Tarheel and my mobile antenna problem was solved. |
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| KC9FSH |
Rating:     |
2008-01-04 | |
| Great antenna for the price |
Time Owned: more than 12 months. |
I purchased this antenna about a year and a half ago from a Hamfest in Madison, WI. I paid about $55 for it and haven't regretted it at all.
I've only used it mobile a couple of times but all of those times it worked great. I got quite a few great reports on 20 and 40.
For a while I had to use this as my primary antenna at my QTH while it was mounted onto my car. It was great for working quite a few PSK31 contacts on 20 meters.
The biggest downfall for this antenna is that it doesn't work well on 80 meters, but that is partially due to the limited ground that is provided by my car.
If this antenna ever failed on me I would gladly pick another one up. It sure beats paying the big bucks for the similar Outbacker antenna. |
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| N8LVR |
Rating:      |
2007-11-29 | |
| Great bang for the buck factor. Very low cost & convenient |
Time Owned: 0 to 3 months. |
Based on the price, and the good reviews on this website, I purchased the HVT-400 about 2 months ago at the Rock Hill, SC hamfest to try out. This antenna is advertised to work on 80, 40, 20, 15, 10, 6, 2, & 440 mhz bands. I have successfully tried all bands except 2 meters & 440 Mhz. I haven't tried those 2 bands yet, because my purpose for this antenna was HF, not VHF/UHF. I have used the antenna the majority of the time on 40 meters on the top of a Ford Escape, and have got very good signal reports. The rest of the HF bands match fine, and should be even more efficient than 40 & 80, which I am happy with already.
Basically the antenna works by using the whole coil for the 80/75 meter band, and using smaller & smaller portions of the coil by plugging the banana plug bypass lead into given set feed points higher up on the coil as you go up in frequency to 40, 20, 15, 10, 6, 2 & 440 mhz. Based on what I read in the other reviews, and what I have experienced myself, I see that this antenna is not entirely consistent with the whip length settings documented in the instructions. For example, at the given documented overall length of 165mm (roughly 65 inches), the antenna is resonant on 80, 40, 20, 15, & 10, but not on 6 meters as advertised at that length. The given whip will easily match on 6 meters, but the wander lead must be used to bypass the coil completely, AND the whip must be lowered so the overall length of the antenna is around 53 inches (quarter wave on 6 meters).
The match is great for the major portions of 20, 15, & 10 meters, and the 2:1 SWR window is about 70 - 80 khz on 40 meters, and 20 - 25 khz on 80 meters . As is required with the vast majority of HF mobile antennas, to get the SWR down flat on 80, 40, & somewhat on 20 meters, it is strongly suggested to use either inductance or capacitance matching network (either with a properly made coil or correct value of capacitors) at the base of the antenna. This is because the resulting feed point impedance, of this much shorter than true quarter wave antenna on these lower frequencies, ends up being much lower than the desired 50 ohms when used in a mobile application. For example, typically the value is around 8 ohms on the 80 meter band. Once the base matching network is applied, you shouldn’t have any problems getting the antenna a perfect match on the advertised bands. Minor tuning can further be done by raising and lowering the whip length.
At first I was frustrated with this antenna, because I found the resonant frequency on the 80 meter band to be way down near the bottom (3.59 mhz). I decided to cut off the shrinkwrap tubing, and slowly remove part of bottom coil to bring the resonant frequency up to 3.75 – 3.85 mhz (depends on how tight the coil is wound around the mast after the necessary approximately 15 coil turns was cut off). The looser the coil, the higher the resonant frequency, but wound tight like it came from the factory, the resonant frequency ended up at 3.76 mhz. After removing the extra wire, it is possible to create another tap point for other points of the 75 / 80 meter band, which I haven't decided if I am going to do. However, I am going to further experiment with using an approximately 20 inch longer whip, which should make the antenna slightly more efficient, especially on the 80 & 40 meter bands. This would make the antenna near 7 feet overall. One could probably easily use a whip to bring the antenna up to 8 feet tall, if they wanted. Additionally, the extra 20 inches will allow me to go towards the bottom of the 80 meter band, if I want to. Of course I might have to adjust the coil for the 40 meter band. No big deal, because this is a good & easy antenna to experiment with.
To conclude, as one person noted, the lower metal whip of the antenna(middle of entire antenna) doesn’t seem to be the strongest. Additionally, the antenna may not be constructed consistently at the factory, and therefore the directions may not be entirely correct in regards to measurements, which may result in the antenna needing coil tweaking/adjustment on 80 meters, or some other band. Even though there are a few shortcomings, given the price of $49 for coverage on all the advertised bands with one antenna, the small physical size, and easy alterability, makes this a very good purchase, which is why I am giving it a 5 rating. It may not give the performance of a screwdriver or bugcatcher antenna (typically $350 more or 8X the cost), but has very good bang for the buck factor, and it doesn’t look bad either, because it is very low profile. It probably doesn’t deserve a 5, but there is no way to rate the antenna a 4.25 or a 4.50.
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| N3DG3 |
Rating:      |
2007-08-27 | |
| Great Value |
Time Owned: 0 to 3 months. |
I am very pleased with the quality, results (especially at the ebb of the Sunspot Cycle) and value of this antenna. It seems to have a similar design to an Outbacker with convenient taps to quickly change bands from 40-2 meters.
It is an OUTSTANDING BUY at R&L for ONLY $45 !!!
Where else can you buy a Brand New HF & VHF Mobile Antenna for that kind of price without paying the premium we all seem to take for granted for overpriced gear and antennas ?! |
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| W8BNL |
Rating:     |
2007-06-14 | |
| Very good for restricted areas. |
Time Owned: 0 to 3 months. |
Well, I made the mistake of moving into a mobile home park that won't allow any "permanent" antennas installed so . . . I clamped one of these to a section of aluminum mast (mil. surplus, about 44" per section) and I put up about 7 sections each night and then take it down in the morning. My Kenwood TS-850SAT tunes the thing very well and I can check into nets on both 40 & 80/75 meters with normally very good signal reports. I am pleased with this and I would have to say that, for the price, this is a very good antenna for my purposes.
Oh yea - I have a 4 foot ground rod into some good soil at the bottom of the mast and have attached a ground to it. The mast sections are light enough to take down and put back up for (fairly) quick band changes.
73 de W8BNL |
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| KB1AWV |
Rating:   |
2007-06-03 | |
| Failed after 6 months but was great while it worked. |
Time Owned: 3 to 6 months. |
This is an update to my previous review above.
The antenna did eventually fail on me after a bit over 6 months (estimate). I believe it shorted or broke internally. I was not able to fix it. The problem may be that ferrule at the bottom.
I may buy another one and give it one more try. For my $50 I had plenty of good QSO's.
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Earlier 5-star review posted by KB1AWV on 2006-02-28
I purchased the HVT-400 about 5 weeks ago. It arrived very quickly from Cheapham.com . I mounted it on a heavy duty Comet lip mount that was already on the liftback of the car, a 2000 Taurus station wagon. This mount previously supported a Diamond HV-7A that broke into several pieces due to its inability to handle the mobile environment. My Comet mount has been fortified by four steel rods welded to each corner. The radio is an Icom IC-706 MK2G. I have mounted a LDG automatic antenna tuner between the rig and the antenna.
I installed the HVT-400 and promptly found that I had no receive at all on the Icom IC-706 MK2G. I found the problem to be the narrow ferrule that joins and insulates the base of the antenna from the main mast. I determined that while I tightened the base to the mount I also inadvertently moved this plastic ferrule about one quarter turn clockwise. When I turned it back, the receive came back. Lesson learned: don’t touch that ferrule.
I then used a SWR meter to tune each band. I was able to get it to <2:1 SWR on 75 m, 20 m, 15 m, and 6 m. The best I got for 40 m was 5.0:1. I could not find a match on 10m. The dealer later told me that I should make the 10-m whip length much longer than suggested in the manual and it should work. I have not tried yet. Also, I used a separate small whip for 6 meters so as to avoid cutting the main whip to size. The antenna was relatively broadband compared to previous experience (for example: 6m – 51.6-54; 75 m ; 3.852-3.873; 20 m – 14.130-14.350). To change bands you must move the wander lead and change the length of the whip by loosening, moving, and then tightening with a hex wrench. The LDG tuner extends my range on each band.
The whip that slides in and out of the mast is secured with just one set screw. The lower portion of it tends to rattle inside the mast; but it does not loosen at all. The mast portion is easily bent. I backed into a small tree limb and stopped almost immediately. The mast was bent. I straightened it (mostly) by hand. The base that screws into the mount remains tight and has never loosened one bit (unlike the Diamond I had).
This antenna has been performing VERY WELL ! I have a 30-minute commute to work each day (7:30 – 8:00 AM EST). I usually make one DX contact each morning when I try and I often do a US contact on the way home at 4:30 PM. My reports are anywhere from 5/5 to 5/9. Contacts have been with the UK, France, Netherlands, Caribbean marine, Bahamas, Cuba, Austria, Japan (from a parking lot at 6 PM), Italy, and others. They all get my call right and have 100% copy.
This antenna is of a style similar to the Outbacker that goes for over $300. It got the Opek HVT-400 for less than $50 delivered! If this lasts for one year I will be ahead. If it breaks after one year, I will purchase another one. Enough said. KB1AWV. 2/28/06 .
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| VA3QV |
Rating:     |
2007-01-10 | |
| Good |
Time Owned: 0 to 3 months. |
I bought this antenna for under $80.00 CDN from a dealer close to Toronto.
I am currently attaching the antennna to the roof of my rental cars using an MFJ Triple Magmount and it works great with my FT857 on 6m to 40m with no extra grounding strap needed.
I do use the LDG Z100 autotuner to extend bandwidth.
On 80m I have had no luck but as I use it on rental vehicles i have not bothered with the extra grounding that has been suggested by both MFJ and the antenna manufacturer.
Performance on the bands I operate on has been excellent. It does seem a bit flimsy and I would not like to have an incident with an overhang or tree branch (thats why not a "5") but for the price I would say its a great bang for the buck.
NO ISSUES FOUND WITH ITS PERFORMANCE
I would buy another
73bob |
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